Abstract
In this study, we explore photoinduced electron transport through a molecule weakly coupled to two electrodes by combining first-principles quantum chemistry calculations with a Pauli master equation approach that accounts for many-electron states. In the incoherent limit, we demonstrate that energy-level alignment of triplet and charged states plays a crucial role, even when the rate of intersystem crossing is much smaller than the rate of fluorescence. Furthermore, the field intensity dependence and an upper bound to the photoinduced electric current can be analytically derived in our model. Under an optical field, the conductance spectra (charge stability diagrams) exhibit unusual Coulomb diamonds, which are associated with molecular excited states, and their widths can be expressed in terms of energies of the molecular electronic states. This study offers new directions for exploring optoelectronic response in nanoelectronics.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 5015-5023 |
| Number of pages | 9 |
| Journal | Nano letters |
| Volume | 18 |
| Issue number | 8 |
| DOIs | |
| State | Published - Aug 8 2018 |
Funding
L.-Y.H. thanks Academia Sinica and the Ministry of Science and Technology of Taiwan (MOST 106-2113-M-001-036-MY3) for financial support. The work at Northwestern University was supported by the Air Force Office of Scientific Research MURI (FA9550-14-1-0003) for applications, and by the Department of Energy Grant DE-SC0004752 for theory. We gratefully acknowledge the computational resources from San Diego supercomputer center (SDSC) through the Extreme Science and Engineering Discovery Environment (XSEDE) program, which is supported by the National Science Foundation (ACI-1053575).
Keywords
- Jablonksi diagram
- Molecular electronics
- energy conversion
- optoelectronics
- quantum transport
ASJC Scopus subject areas
- General Chemistry
- Condensed Matter Physics
- Mechanical Engineering
- Bioengineering
- General Materials Science